Electromagnetic vibrator.



N0- 806,636. PATENTED DEC. 5, 1905.

R. GARLSTEDT.

ELECTROMAGNETIC VIBRATOR.

APPLICATION FILED AUG. 22, 1904. RENEWED MAY 16, 1905.

witmeooeo that shown in Fig. 1.

UNITED STATES PATENT OFFICE.

ELECTROMAGNETIC \IIBRATOR.

Specification of Letters Patent.

Patented Dec. 5, 1905.

Application filed August 22, 1904. Renewed May 16, 1906. Serial No. 260,724.

To crZZ 'LUhOTIb it may concern:

Be it known that I, RAGNAR CARLsTnD'r, a subject of the King of Sweden and Norway, residing in Jersey City, Hudson county, New Jersey, have invented certain new and useful Improvements in Electromagnetic Vibrators, of which the following is a specification.

This invention relates to the class of electromagnetic vibrators wherein is employed a make-and-break device, the magnet moving an armature in one direction until the circuit is broken at a back contact, when a spring or gravity returns the armature and closes the circuit again. Thus vibration of the armature is produced, the rapidity whereof may be modified by suitable regulating means. Such a vibrator may be employed for many uses as, for example, winding intermittently the spring of a clock; but the present invention does not relate to the application thereof to any special or particular art.

The object of the invention is, broadly expressed, to insure at all times a perfect electrical contact between the contact devices and to provide means for maintaining said contact for a predetermined and desired length of time While the armature is in motion. In the ordinary vibrator of an electric bell, for example, the circuit is made and broken almost instantaneously, but in the present construction the circuit is closed, the magnet thus energized, and the rocking armature set in motion by the lines of magnetic force. The circuit remains closed during this movement and is only broken by the yielding contact encountering an insulating block or plate. The spring or weight then returns the rocking armature again to its primary contact position.

In the accompanying drawings,which illustrate embodiments of the invention, Figure 1 is a side elevation of the device in its preferred form. Figs. 2 and 3 are views showing the rocking armature in different positions from Fig. 4C is a plan, and Fig. 4" is a detail view of the armature-spring on a larger scale than Fig. i. Fig. 5 illustrates a slight modification wherein the tip of the contact-piece is of non-magnetic metal. Figs. 6 and 7 illustrate another modification where the contact is made at the pole-piece.

Referring primarily to Figs. 1 to 45, 1 and 1 designate the two coils of a horseshoe-electromagnet, of which 2 and 2 are the respective pole-pieces on the core of the magnet. G designates any form of generator or source of electricity which supplies current to the coils of the magnet. 3 is an armature mounted to rock on journals 4: in bridge-plates 5, of non magnetic metal, connecting said polepieces. There is a spring 6 (seen in Figs. 4 and 4:) about one of the journals of the armature, which spring tends to rock the latter to the primary contact position. (Seen in Fig. 1.) Any suitable spring may be employed for this purpose, but that shown in Fig. 4:, which is a detail view on a large scale, is a volute spring secured at one end to the journal 4; and at the other end to an inclosing casing 7 on the bridgeplate 5 at that side. On the armature or its journal is a slotted plate 8, the slot in which is engaged by a stop-pin at 9 in one of the plates 5, thus serving as a limiting device for the rocking armature. Any equivalent limiting device may be substituted for this. The wire to of the coil I is electrically connected with the pole-piece 2 and through the bridge-plates 5 the current is carried to the armature 3, which thus becomes one terminal of the circuit. The wire 10 of the coil 1 is insulated from the pole-piece 2 and is connected electrically with a contact-piece 10, of soft iron. This contactpiece or subarmature has a spring-hinge connection 11 with the pole-piece 2, but is insulated therefrom, as seen in Figs. 1, 2, and 3. The free or contacting end of the piece 10 extends out over the rocking armature and is so disposed that when the spring 6 rocks the armature to the position seen in Fig. 1 the free end of the contact-piece will be near enough for the armature to move into contact with it, and thus close the circuit, the armature forming one terminal of the magnetcircuit and the contact-piece the other terminal thereof. The magnet being now excited by the current flowing through its coils. the lines of force rock the armature in the other direc tion; but this does not immediately break the circuit for the reasons now to be explained. As the armature 3 and contact-piece 10 are both of soft iron or magnetic metal, the armature becomes a magnet and attracts the contactpieee strongly, thus maintaining the electrical contact and the circuit closed until the tip of the piece 10 slides back over the surface of the armature to the point seen in Fig. 2. At this point, which is near the limit of movement of the rocking armature in that direction, the tip of the contact-piece rides up on a slightly-convex plate 12 of insulating material set in the armature, and this breaks the circuit. In its sliding movement over the armature the spring-hinge 11 flexes to allow of contact being maintained; but as soon as the circuit is broken the contact-piece is lifted by the spring at 11, and the contact-piece stands clear, as in Fig. 3, of the armature. The extent of movement of the armature in rocking will be by preference a little greater when under the influence of the spring 6 than is necessary to effect a contact of the armature with piece 10, so that the momentum of the moving parts may cause the tip of the piece 10 to rub over the surface of the armature a little beyond the primary contact-point as well as over the surface between said contact-point and the insulating-piece 12. This rubbing of the surfaces insures at all times a good electrical contact, and the maintenance of the contact for a predetermined time permits of an extended movement of the armature as well as a relatively slow and measured movement thereof, which is very desirable insome applications of such an invention. This slowing down of the movement may be effected in various ways known to those skilled in the art, and no device for the purpose has been shown herein. A balance-wheel geared to the journal of the armature would serve as a retarding means.

It is not essential that the tip of the contact-piece shall be of magnetic metal. In Fig. 5 a construction is shown wherein the'contactpiece 10 has a tip 10 of non-magnetic metal; but in this case the eifect is the same, as the soft-iron body of said piece occupies a position over and adjacent to the pole-piece 2, and when the circuit is completed through the coils of the magnet the said pole-piece will attract the body of the contact-piece, and thus preserve the contact of its tip 1O with the armature.

Figs. 6 and 7 show another form of the invention where the spring contact-piece is carried by the armature and the contact is made at the pole-piece. Fig. 6 is asectional elevation and Fig. 7 a sectional plan. In this construction the bridge-plates 5 are insulated from the pole-pieces, as indicated at 13 in Fig. 7. The wire Q02 connects with one of said bridgeplates, and the wire w connects with the polepiece 2, which forms one of the terminals of the magnet-circuit. The current .may flow from the wire 20 through the bridge-plate 5, armature 3, and connecting-spring 11 to a contact-piece 10, of soft iron, which forms the other terminal of the circuit. This contact-piece 1O is carried by the armature 3 and plays in a slot or groove 14: in the pole-piece 2". The bottom of this slot forms a surface 15 which is eccentric to the curved path traversed by the end of the rocking armature. When the armature-spring rocks the armature to the position seen in Fig. 6, the tip of the piece 10 comes in contact with surface 15 and completes the circuit, thus energizing the magnet. The armature now rocks in the other direction and the tip of the contactpiece plays over the surface 15, its spring flexing until the tip of the contact-piece rides up on the insulating block or plate 12 set in the surface 15, when the circuit will be broken and the contact-piece will spring away from the surface 15 and allow the armature-spring to rock the armature back to the position seen in Fig. 6.

Other ways of varying the details of construction will doubtless occur to those skilled in the art. The plate 12, of insulating material, is made, by preference, slightly convex, so as to take under and lift or move away the tip of the contact-piece; but this convexity is not absolutelyessential.

It will be obvious that in the device described the special feature is the terminals containing iron attracted and held in rubbing contact by the magnetic attraction during the entire period of excitation of the magnet. The means which will be required to antagonize the magnetic attraction, here shown as springs, may of course be an equivalent, such as weights or gravity. Springs are most convenient in the special construction shown.

Having thus described my invention, 1 claim 1. A device of the character specified, comprising an electromagnet, having a terminal which contains iron and which is movable in one direction when the magnet is excited, antagonistic means for moving said terminal in the other direction when the excitation ceases, another terminal which contains iron and is within the field of force, one of said terminals being in the path of the other and their contact effected by the said antagonistic means, means antagonistic to the magnetic attraction operating on one of said terminals, and means for breaking the magnet-circuit, one of said terminals being held in rubbing contact with the other by magnetic attraction during the entire period of excitation.

2. A device of the character specified, having an electromagnet with iron terminals in its circuit, which are put in contact by the movement of the armature and held in rubbing contact during the movement of the armature under the influence of magnetic attraction, a spring which antagonizes the attraction of one terminal to the other, and means, controlled by the armature for breaking the magnet-circuit.

3. An electromagnetic vibrator, having a horseshoe-magnet with pole-pieces, a rocking armature between said pole-pieces, an armature-spring antagonizing the attraction of the pole-pieces, a contact-piece forming one of the terminals of the magnet-circuit and having iron within the field of force of the magnet, said contact-piece being provided with a spring, which antagonizes the magnetic attraction, and being held in contact with the other iron terminal of the magnet-circuit when by its spring, a spring which antagonizes the efiect of magnetic attraction on the contactpiece, and a piece of insulating material in 5 the armature in the path of the contact-piece, for breaking the circuit.

In witness whereof I have hereunto signed my name, this 8th day of August, 1904, in the presence of two subscribing witnesses.

RAGNAR GARLSTEDT.

Witnesses:

HENRY CONNETT, BENJAMIN H. HOLT. 

